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VPN - same local subnets

I am configuring a VPN for a remote office to connect to the home office. The ISP assigns a 192.168.1.X internal address and that is the same as the remote network. The VPN will come up, but the computer can't access any resources on the network. I tend to think I am missing something easy.

Here are the address:

Local internal:

Nat'd address from router:

Remote internal: 192.168.1.X

On the remote network, there is an AS400 that needs accessed as well as an Exchange Server.


Re: VPN - same local subnets

it doesn't work because of the subnets overlapping.

e.g. when remote pc sends an request to the email server, it looks up the destination ip. since the destination ip is the same as the lan, the remote pc will send an arp request attempting to resolve the mac address. in other words, the remote pc will not send the request to the router, and hence it will not be encrypted and sent to the email server via the vpn tunnel.

to resolve the issue, i believe you need to change the subnet range.